Residential Construction Budget Cost Calculators

There are many factors that can influence construction costs. Geographic location, level of detail and workmanship, and interior finishes can cause construction costs to vary widely. Calculators are based on construction cost data collected from the actual costs of similar scope projects, the prevailing data on economic conditions, and the good faith professional judgement of WJM. The calculators are periodically adjusted based on changes in data. (Last adjusted Dec. 2014)

Instructions and Disclaimers--

Normal, middle-range,"85th percentile" [1], complete, fixtured, and finished occupiable residential 1 and 2 family home construction is the basis for these calculators. The normal things that most people want. This includes basic finishes, walls, base and trim moldings, basic flooring and bath tile, ceilings, painting, electrical, basic lighting fixtures, heating and air conditioning, basic plumbing fixtures, doors, windows, exterior vinyl type siding, ashphalt shingle roofing. Anything not included in this list is not part of these calculators. If your personal taste tends toward more expensive features and finishes, this is not reflected and must be added. The idea is to provide a useful tool for someone who wants a general idea of what their project might cost to build.

The cost of kitchen cabinets, appliances and countertops is NOT part of these calculators. New or redone kitchen costs must be added. Land clearing, landscaping plantings and other site related work such as pools and retaining walls are NOT part of these calculators.

Contractors will generally exclude the cost of lighting fixtures, plumbing fixtures, flooring, and painting. A contractor's initial estimated cost will likely be lower than what these calculators show for this reason. THESE BASIC ITEMS ARE factored into the calculators since it is assumed that complete and finished construction is the goal. You need to be aware of this. When dealing with contractors, it is not just "how much" but also, "what specifically does that cost include and NOT include".

As projects get larger, economy of scale factors in. A larger project will have a lower overall unit cost. The calculators are broken down into square foot ranges to account for this effect.

Every project has a wide range of variables and not all variables can be factored into these simplified tools. You should NOT rely only on this information alone to make cost decisions. These calculators are provided to help people develop a general understanding of costs and are not meant to replace good professional advice.

Remember, the proven way to get the most for your money is by Competitive Bidding. Contractors compete against eachother for the opportunity to construct your project. Generally, it is NOT in the best interest of the "low bid" contractors to exactly define the work when bidding, since it allows you to directly compare prices BEFORE you select the contractor.

Good professional building contractors will also use these calculators so they may better assist their clients in understanding the differences in how costs are calculated. Good professional building contractors in competitive bidding situations can be at a disavantage when less qualified "low bid" contactors bid lower and try to make up the money during the construction through "extra charges".

An architect can assist you in understanding how extra charges can be avoided and minimized. This advice can save you thousands of dollars while maintaining good quality and construction value.

The cost calculators below will give you a general idea of what your construction may potentially cost.

You won't know the exact construction cost until you have completed the competitive bidding process.

You cannot successfully complete the competitive bidding process without a detailed set of professionally prepared construction drawings. Click this link for more cost info.

--IMPORTANT-- These pages are for general use and not meant as a solicitation to provide architectural services in any jurisdiction other than those in which WJM is licensed to practice architecture.

--IMPORTANT-- Green sustainable design features are NOT factored into these calculators. Energy conserving green sustainable design features will likely add to the initial construction cost, but pay for themselves over time through savings (return on investment or "ROI" ). These systems and features can vary widely based on geographic location. Local climactic knowledge is vital to determining the costs and benefits of green sustainable design features. These calculators include features necessary to meet the buidling code minimum energy conservation requirements.

--IMPORTANT-- The calculators assume the work will be constructed and managed by a good professional construction contractor with proper license, insurance, and building permits as required by each jurisdiction.

NOTE: Calculator values across states can vary, more rural areas will tend lower in the range, more urban areas will tend higher in the range. Construction in wilderness areas far from roads / rail-lines and with limited access to normal delivery of materials are not accounted for in these calculators.

Hypothetical example of how to use these calculators:

The example project is a new family room addition with a full bath, added to the rear of an existing home. An existing rear wall will connect the addition to the house, so the alteration to remove this wall and renovation of the 15 foot wide existing space adjacent is also proposed. The addition siding will match the existing vinyl house siding. The addition roofing will match the asphalt shingles of the existing house. Heating and air conditioning will be expanded and extended into the new space. Windows and exterior french glass doors will let in light and provide access into the rear yard from treated wood steps. The basic 3 fixture bath, tub shower, toilet, sink vanity will have basic tile floor and walls. The new room and adjacent space will have painted walls and ceiling, and basic red oak hardwood flooring. Basic recessed lights, electrical outlets, switches, cable tv wiring included.

The proposed new addition is 25 feet by 25 feet with a new basement space under that will be unfinished. The ceiling height will be raised cathedral type and be higher than the existing house ceiling height of 8 feet.

STEP 1-- 25 times 25 = 625 sf. This is the sf of new finished living space.

STEP 2-- 10 times 625 sf = 6250 cubic feet. This is the volume cubic footage of the new finished living space with a sloping cathedral ceiling average height 10 feet.

STEP 3-- 25 times 15 = 375 sf. This is the sf of the 15 foot wide altered renovated existing living space adjacent to the addition.

STEP 4-- 8 times 375 sf = 3000 cubic feet. This is the volume cubic footage of the altered renovated existing living space.

This example project does not include renovation of the kitchen. The cost of kitchen cabinets, appliances and countertops is NOT part of these calculators. Kitchen costs must be added. Land clearing, landscaping plantings and other site related work such as pools and retaining walls are NOT part of these calculators.

Every project has a wide range of variables and not all variables can be factored into these simplified tools. You should NOT rely only on this information alone to make cost decisions. These calculators are provided to help people develop a general understanding of costs and are not meant to replace good professional advice. Call WJM with questions regarding your specific project requirements.

Footnotes:

[1] 85th percentile -- This refers to a method of statistical analysis by which the extreme highs and lows of a data set are excluded leaving data that more accurately represents middle range.